Resistion:- No not just feedback, learning is a combination of positve and negative feedback at the same time within an array, plus a little addition. Components, like PCM, ReRAM, CbRAM, CnRAM, and the spintronics devices FeRRAM and MRRAM all offer the ability to permanently record the results of that feedback and learn a little more efficiently than the silicon equivalent. One measure of IMECs success as well as the claims of others will be the silicon overhead required to utilize the capability.